Epicardial percutaneous device for electrical cardiac therapy

ABSTRACT

An apparatus and method for Cardiac Resuscitation of an arrested heart, for Percutaneous Internal Direct Epicardial Defibrillation, Cardioversion and Pacing with electrodes placeable directly into the chest cavity onto the epicardium via a device entering the chest in a specific area of the anterior chest wall via blunt dissection rapidly creating a passage of negligible size in the chest wall for the introduction of the electrodes, without the need for thoracotomy or for sternotomy and without requiring the use of sharp surgical instruments and without causing pneumothorax. Due to its rapidity of implementation, its safety and simplicity of application, the device can be used by Paramedics in the field at the scene of a cardiac arrest, where the resuscitation efforts are more likely to succeed, for internal direct epicardial defibrillation, cardioversion and pacing.

FIELD OF INVENTION

[0001] This invention relates to electrical cardiac therapy devices,specifically to emergency defibrillators, cardioverters and pacemakers.

BACKGROUND-DESCRIPTION OF PRIOR ART

[0002] Electrical therapy is nowadays commonly used in cardiac therapy,specially in cardiac resuscitation. Defibrillation, cardioversion andpacemaker therapy play a major role in cardiac resuscitation.Defibrillators and cardiac pacemakers are indeed common devices in theemergency armamentarium. Electrical therapy has proved over the last twodecades to be indeed often lifesaving in cardiac arrest settings.Cardiac arrest can results from a variety of cardiac arrythmias allamenable to electrical therapy. These arrythmias include ventricularfibrillation, ventricular tachycardia, ventricular asystole and highdegree heart blocks. A defibrillator is a device that administers acontrolled electrical shock to patients to terminate a cardiacarrhythmia. The technique of administering the electrical shock isusually referred to as defibrillation if it used to terminateVentricular Fibrillation or pulseless Ventricular tachycardia. andreferred to Cardioversion if it is administered for other cardiacarrythmias, typically atrial fibrillation, atrial flutter, orventricular tachycardia. Typically, in defibrillation the electricalshock is unsynchronized with the cardiac cycle while in cardioversionthe electrical shock is delivered in synchronization with the cardiaccycle, at a specific electrical stage of the cardiac cycle.

[0003] The defibrillator basically consists of a charging circuit thatgradually builds electrical energy to a preset level on a storagecircuit. The storage electrical energy is then delivered to the patientthrough a discharge circuit. The electrical stored energy is deliveredvia conductive paddles applied to the chest or back of a patient in theExternal Defribillator. Another type of Defibrillator is the AutomaticImplantable Cardioverter-Defibrillator which consists of a pulsegenerator with both sensing and shocking electrodes. In the AutomaticImplantable Defribillator the shocking electrodes are usually twoepicardial patches placed in anteroposterior position over the heartsurface or one epicardial patch and another electrode, the so calledtransvenous spring electrode, placed in the right ventricular apex, allimplanted by thoracotomy or sternotomy i.e. by surgical opening of thechest. Rarely direct epicardial defibrillation. i.e. defibrillation withtwo epicardial paddles applied directly over the heart inanteroposterior position is implemented, the indications being traumaticcardiac arrest, open chest surgery or, extremely rarely, in medicalcardiac arrest during open chest cardiac massage.

[0004] The energy required for Direct or Internal Defibrillation of theheart in these cases is by far less than the energy required withExternal Defibrillation. Due the fact the paddles are directly appliedover the heart obviously the impedance, i.e. the resistance to currentflow, is greatly reduced in respect to the commonly used ExternalDefibrillators. There are indications that Direct or InternalDefibrillation is more effective that External Defibrillation.Unfortunately due the fact that Direct or Internal Defibrillation can becarried out only in patients victim of cardiac arrest via thoracotomy,i.e. via the surgical opening of the chest, its applications areseverely limited and, practically, it can be carried out only in case oftraumatic cardiac arrest or in patients whose heart arrested duringcardiac surgery in the operating room. Due to the fact that Direct orInternal Defibrillation via thoracotomy cannot obviously be carried outin the field at the site of a cardiac arrest nor in most cases inEmergency Departments as thoracotomy is a highly invasive procedure withhigh morbidity and mortality, the usefulness of Direct of InternalDefibrillation is restricted to a very small number of patients leavingout the greater majority of patients victim of cardiac arrest.

[0005] Pacemakers are medical devices that deliver an electricalstimulus through electrodes to the heart causing electricaldepolarization and subsequent cardiac contraction. Emergency cardiacpacing is required in patients whose primary problem is cardiac impulseformation and /or conduction such as hemodynamically compromisingunstable bradycardia, high degree of heart block, bradysistolic cardiacarrest and also refractory tachycardias. Emergency Temporary CardiacPacemakers are named according to the location of the electrodes and thepathway the electrical stimulus travels to the heart. They are named:Transcutaneous when the electrodes are placed on the skin of theanterior chest wall and back of a patient, Transvenous when theelectrode tip is positioned in the right ventricle or right atrium orboth, Transthoracic when the electrodes are placed through the anteriorchest wall into the myocardium, i.e. the heart muscle, Epicardial whenthe electrodes are placed on the surface of the heart, Transesophagealwhen the electrodes are positioned within the esophagus.

[0006] As Internal Defibrillation, Epicardial pacing, i.e. cardiacpacing with the electrodes placed directly onto the epicardium orthrough the epicardium, is almost exclusively carried out during openchest surgery for resuscitation of patients with penetrating chesttrauma. Despite dramatic improvement has been reported followingepicardial pacing, its application is restricted to only an handful ofpatient due to the obligate requirement of opening surgically the chestfor placing the pacing electrodes onto the heart surface.

[0007] No epicardial electrical therapy device, Defibrillator or Cardiacpacer is known to have the electrodes placed onto the heart surfacewithout the surgical opening of the chest.

OBJECTS OF THE PRESENT INVENTION

[0008] As above pointed out, there are studies documenting thedramatically superior efficacy of epicardial pacing versus thetranscutaneous pacing, and there are strong indications that epicardialdefibrillation carried out within a reasonable time of onset of acardiac arrest is effective and indeed more effective than the presentlynormally used method of external defibrillation.

[0009] At present time, epicardial defibrillation and or epicardialpacing can only be carried out via surgical opening of the chest withsharp instruments. Such a procedure, besides being associated with highmorbidity and mortality, has the unavoidable drawback of having to becarried out only in operating rooms and rarely in Emergency Departments.Due to the invasiveness character of the procedure, epicardialdefibrillation and or pacing is presently rarely carried out and only incases when open chest cardiac massage via thoracotomy is carried out.

[0010] It is an object of the present invention to provide an electriccardiac therapy device for defibrillation, cardioversion and pacing withat least one electrode being placeable directly onto the heart surfacevia introduction into the chest cavity with means of blunt dissection ofthe chest wall without surgically opening the chest.

[0011] It is an object of the present invention to provide an electriccardiac therapy device for defibrillation, cardioversion and pacing withat least one electrode being placeable directly onto the heart surfacevia introduction into the chest cavity without the requirement ofsurgically opening the chest.

[0012] The fundamental and unique feature of gaining access to the chestcavity and to the heart without surgically opening the chest, via bluntmeans for dissection and blunt means for entry into the chest cavity forthe purpose of epicardial defibrillation and or pacing is not known inany prior art.

[0013] The ability of gaining access to the chest cavity via blunt meansfor dissection and blunt means for entry into the chest cavity iscritical in rendering epicardial defibrillation, cardioversion andpacing a procedure that can be practically implemented in large numberof patients. The procedure can be carried out in patients in the fieldat the scene of a cardiac arrest where resuscitative efforts are morelikely to succeed.

[0014] It is an object of the present invention to provide an electriccardiac therapy device for defibrillation, cardioversion and pacing withat least one electrode being placeable directly onto the heart surface,such electrode placement being carried out safely via blunt means ofdissection in a specific area of the chest wall without causing injuriesto the chest wall structures, to the heart and to the otherintrathoracic organs and without causing pneumothorax, i.e. collapsingof the lung.

[0015] It is an object of the present invention to provide an electriccardiac therapy device for defibrillation, cardioversion and pacing withat least one electrode being placeable directly onto the heart surfacerapidly and safely at the site of the cardiac emergency situation.

[0016] Buckman and Badellino disclosed in their Pat. No. 5,484,391, No.5,571,074 and No. 5,582,580, a method and apparatus for direct cardiacdefibrillation and pacing associated with their disclosed direct manualcardiac compression device. The device of Buckman and Badellino isdisclosed to be inserted into the chest cavity onto the heart viaopening the chest via surgical means, precisely making an incision inthe skin of an intercostal space and surgically separating theintercostal space for the purpose of inserting the device. The apparatusand method disclosed by Buckman and Badellino, although it presents someadvantages over the open chest cardiac massage and over theimplementation of epicardial defibrillation and or pacing viathoracotomy, still has the unavoidable drawback of having to be carriedout by way of a surgical opening of the chest with a surgical knife withall the complications associated with the surgical opening of the chestand with the unavoidable disadvantage of having to be implemented onlyin a hospital setting, and not at the scene of a cardiac arrest whereresuscitative efforts are more likely to succeed.

[0017] It is an object of the present invention to provide an epicardialdevice for electrical cardiac therapy that can be used in associationwith all the cardiac resuscitation devices for percutaneous directcardiac massage disclosed by Zadini et Al. in their issued Pat. No.5/466,221, in their copending patent application Ser. No. 08/100,573filed on Jul. 30, 1993 allowed and abandoned, in their copending patentapplication Ser. No. 08/600,306, a Continuation of patent applicationSer. No 08/100,573, filed Feb. 12, 1996, now allowed, and in theircopending patent application Ser. No. 08/555,589 filed on Nov. 13, 1995and now pending. All the above references have the very important commonfeature of placing an expandable member into the chest cavity in frontof the heart for the purpose of compressing and decompressing the heartvia means of blunt dissection through the chest wall and blunt entryinto the chest cavity. No other known resuscitation device or methods ofcardiac resuscitation has the feature of placing the cardiaccompression-decompression member for direct cardiac massage into thechest cavity by means of blunt dissection of the chest wall and bluntentry into the chest cavity.

[0018] No other cardiac resuscitation device is known to have thefeature of being operated safely effectively and swiftly at the scene ofthe cardiac arrest where the chances of survival are greater.

[0019] The combination of the epicardial percutaneous device forelectrical cardiac therapy with the cardiac resuscitation device forpercutaneous direct cardiac massage makes epicardial defibrillation,cardioversion or pacing a practical procedure usable in conjunction andconcurrently with direct cardiac massage as the arrested heart mayrespond to either electrical therapy or direct cardiaccompression-decompression. As pointed out above, at present epicardialdefibrillation and or pacing can only be carried out via surgicalopening of the chest with sharp instruments. Such a procedure, besidesbeing associated with high morbidity and mortality, has the unavoidabledrawback of having to be carried out only in operating rooms and rarelyin Emergency Department. Due to the invasiveness character of theprocedure epicardial defibrillation and or pacing is presently rarelycarried out and only in cases when open chest cardiac massage viathoracotomy is carried out.

[0020] Due to its ability of being implemented with minimal invasivenessand safely without damaging intrathoracic organs including the heartowing to the features of gaining access to the chest cavity by bluntdissection and blunt entry, the potentially highly effective emergencyprocedure of epicardial defibrillation and/or pacing with the presentinvention can be implemented even at the scene of a cardiac arrest bytrained personnel such as paramedics at the earliest time when itsusefulness is greater.

[0021] Again, the fundamental and unique feature of gaining access tothe chest cavity and to the heart via blunt means for dissection of thechest wall and blunt means for entry into the chest cavity for thepurpose of epicardial defibrillation and or pacing is not known in anyprior art.

[0022] It is important to point out that gaining access to the chestcavity with a sufficiently small size blunt means through the “trigonumsine pleura”, which is an area in the inner aspect of the anteriorthoracic wall void of lung tissue and of its lining, i.e. pleura,guarantees, among the others, the unique advantage, in respect ofmethods of surgically opening the chest, of not causing the complicationknown as pneumothorax, i.e. collapse of the lung, which is anunavoidable complication when the chest is opened surgically.

[0023] The ability of gaining access to the chest cavity via blunt meansfor dissection and blunt means for entry into the chest cavity iscritical in offering the significant dual advantage of rendering twopotentially highly effective procedures such as direct heart massage anddirect epicardial electrical therapy concurrently practicallyimplementable in large number of patients. Both procedures can becarried out in patients in the field at the scene of cardiac arrestwhere resuscitative efforts are more likely to succeed.

DRAWING FIGURES

[0024]FIG. 1 shows a cross sectional view of an embodiment of the devicewith its stem tip within the chest cavity prior to deployment of the twoelectrodes on the epicardium.

[0025]FIG. 2 shows a view of the two deployed electrodes on theepicardium ready for electrical therapy.

[0026]FIG. 3 shows a cross sectional view of the thoracic cavity withthe two electrodes deployed and positioned on the epicardium.

[0027]FIG. 4 shows a cross sectional view of the thoracic cavity with analternative form of the device of FIGS. 1 to 3 showing its singleepicardial electrode and its other electrode applied on the skin of theback of the patient.

[0028]FIG. 5 shows a cross sectional view of an alternative form of theelectrical therapy device of FIG. 1 to 4 in combination with apercutaneous direct cardiac massager at rest, ready to be used..

[0029]FIG. 6 shows a cross sectional view of a detail of the device ofFIG. 5.

[0030]FIG. 7 shows a cross sectional view of another detail of device ofFIG. 5.

[0031]FIG. 8 shows a cross sectional view of a chest of a patient withthe device of FIG. 5 in use after penetration of its tip into the chestcavity and at an intermediate inflation stage of the expandable member.

[0032]FIG. 9 shows a cross sectional view of a chest of a patient withthe expandable member of device of FIG. 5 fully expanded.

[0033]FIG. 10 shows a view of a device for opening a passage through thechest wall and entering the chest cavity by blunt dissection to enablethe insertion of the electrodes into the chest cavity onto theepicardium.

[0034]FIG. 11 shows the electrical component of the device of FIG. 10.

[0035]FIG. 12 shows a schematic cross sectional view of an alternativeform of the electrical therapy device of FIGS. 1 to 4 in combinationwith an alternative form of the percutaneous direct cardiac massagerillustrated in FIGS. 5 through 9 at an initial stage of operation.

[0036]FIG. 13 shows the device of FIG. 12 at a further stage ofoperation.

DETAILED DESCRIPTION OF THE INVENTION

[0037] In that form of the present invention chosen for purpose ofillustration an epicardial percutaneous device for electrical cardiactherapy indicated generally at 1200′ is shown in FIG. 1.

[0038] As shown in FIG. 1, which is a cross sectional view of thedevice, the device, generally indicated at 1200′, is composed of twomain components, stem member 1202′ and a set of two pairs of divergingelectrode-ribs 1216′. Stem member 1202′, of general cylindrical hollowshape, comprises hollow stem 1203′, distal end or stem tip 1201′ andproximal end 1205′. Proximal end 1205′ of stem member 1202′, is securelyconnected to handle 1206′. Within hollow stem 1203′ is slideably mountedrod 1210′. Rod 1210′ is of generally cylindrical shape having an arrayof notches 1209′ on its proximal segment for engagement with locking tab1246′, as it will be described below. Proximal ends 1231′ of divergingelectrode-ribs 1216′ are firmly attached to distal end 1218′ of rod1210′. Hollow stem 1203′ is formed with longitudinal slit 1213′ forhandle arm 1212′ of handle 1211′. Longitudinal slit 1213′ has proximalend 1219′ and distal end 1220′. Locking means or tab 1246′ with flexiblearm 1229′ is fastened via pin 1243′ to hollow stem 1203′ and has arresttooth 1245″ engaging opening 1242′ in hollow stem 1203′. Tab 1246′ hashandle 1208′ for manual release of locking tab 1246′.

[0039] Stem tip 1201′ is of general spheroid, elliptical cross sectionor ovoid shape. The roundness of the stem tip 1201′ confers theimportant feature of bluntness to stem tip 1201′ and, as it will bedescribed below, it will consent to gain access to the chest cavity bydissecting the chest wall by blunt dissection, which is critical inavoiding injuries to the structures of the chest wall and to theintrathoracic organs, such as the heart. Stem tip 1201′ has openings1238′ for passage of electrode-ribs 1216′.

[0040] Stem end or tip 1201′, firmly attached to distal segment 1233′ ofhollow stem 1203′ of stem member 1202′ is of greater width thancontiguous distal segment 1233′.

[0041] Electrode-ribs 1216′ are made of resilient material such as steelor suitable medical grade plastic. If made of steel they requireinsulating coat. Also, fiberoptic cables can run with electrode-ribs1216′ within hollow stem 1203′, or alternatively electrode-ribs 1216′can be made of suitably resilient fiberoptic material to provideendoscopic also visualization of the intrathoracic organs such as theheart and the epicardium for confirmation of proper positioning of padsor webs 1222′ on the epicardium. All electrode-ribs 1216′ are connectedat their respective proximal ends 1225′ to distal end 1218′ of rod1210′, slideable, as already described, within hollow stem 1203′ of stemmember 1202′.

[0042] As best seen in FIGS. 2 and 3, electrode-ribs 1216′ are in a setof two pairs and each rib has distal blunt end 1215′. Each pair ofelectrode-ribs 1216′ has, in correspondence of their distal segment, web1222′ of grossly triangular shape, made of electrical conductivematerial. As best seen in FIG. 3, web 1222′ has an epicardial contactingand conducting surface 1260′ and an electrically insulated oppositesurface 1261′. Webs 1222′ function as electrodes for transmittingelectrical current to the heart for defibrillation, cardioversion andpacing, and also function as sensors of cardiac electrical activity andalso can function as sensors of epicardial contact pressure.

[0043] An insulated electrically conductive cable 1270′ is connected toeach web 1222′ and is mounted along electrode-ribs 1216′ within hollowstem 1203′ to exit through opening 1207′ formed in hollow stem 1203′ tobe connected to an external electrical therapy device such as adefibrillator-cardioverter, a cardiac pacing device or to anelectrocardiographic monitoring device.

[0044] Prior to use each pair of electrode-ribs 1216′ is retained intheir entire length within hollow stem 1203′ and forced to bunchtogether very close one to another, against their resiliency which urgesthem to diverge outwardly one from another in correspondence of theirdistal segments.

[0045] Description of operation of device of FIGS. 1 to 4.

[0046] The operator makes a small superficial incision in the patient′sskin on the anterior chest wall preferably in the left parasternalregion along the left parasternal border, in a skin area correspondingto the intrathoracic anatomical area designated as “trigonum sinepleura”, i.e. “triangle without pleura”. Usually such area correspondsto the fourth and fifth intercostal space. However anatomical variantsare possible where the trigonum sine pleura extends to contiguousintercostal spaces. Access to the chest cavity can also be gainedthrough the subxyphoideal region.

[0047] A skin incision, approximately ⅜″ long or less, is carried out onthe very superficial layer of the skin, to a depth comprised ordinarilybetween {fraction (1/16)}″ to ⅛″ for the purpose of overcoming theresistance of the skin encountered by the blunt tip 1201′ of the devicein entering the chest wall of a patient. The superficial skin incisionis carried out with a suitable surgical instrument such as a lancet orthe tip of a surgical knife preferably provided with an arrest toprevent deeper penetration.

[0048] Spheroidally shaped tip 1201′ of device 1200′ is then inserted bythe operator into the skin incision. Operator then carefully graduallyadvances the device through the chest wall 107 by blunt dissection byholding the device by hand in close proximity of the chest wall 107 andforcing the device downward through the chest wall thickness. By suchmethod the device can only be advanced in steps of predetermined amountequal to the distance between the chest wall and the hand of theoperator holding the device in proximity of the chest wall. In such afashion the device is indeed advanced through the chest wall in agradual stepwise manner toward the chest cavity. A number of moresophisticated mechanisms of gradual advancement of the blunt stem tipthrough the chest wall, achieving a high degree of safety andeffectiveness, can be used, such as the mechanisms disclosed by Zadiniet Al. in their issued Pat. No. 5/466,221, copending patent applicationSer. No. 08/100,573 filed on Jul. 30, 1993 allowed and abandoned,copending patent application Ser. No. 08/600,306, a Continuation ofpatent application Ser. No. 08/100,573, file Feb. 12, 1996, now allowed,and copending patent application Ser. No. 08/555,589 filed on Nov. 13,1995 and now pending.

[0049] Stem member 1202′ is advanced by blunt dissection through thethickness of chest wall 107 until blunt entry of the means which opensthe passage through the chest wall, i.e. stem tip 1201′, is gained intochest cavity 110. Being stem tip 1201′ of hollow stem 1203′ of a greaterwidth than distal contiguous segment 1233′ of hollow stem 1203′, thestem tip 1201′ allows the operator of the device, upon entry of tip2001′ into the chest cavity 110, to tactually sense entry of the bluntdistal stem end 1201′ into the chest cavity by the sudden fall ofresistance to forward and sideways movement of stem tip 1201′, saidresistance to forward and sideways movements being present duringpassage of said stem tip 1201 ′ through chest wall 107, due toconstraint exerted by chest wall tissues upon stem tip 1502 during itspassage through chest wall 107.

[0050] A number of more sophisticated mechanisms for sensing entry ofthe stem tip into the chest cavity, achieving a high degree of safetyand effectiveness can be used, such as the mechanisms disclosed byZadini et Al. in their issued Pat. No. 5/466,221, in their copendingpatent application Ser. No. 08/100,573 filed on Jul. 30, 1993 allowedand abandoned, in their copending patent application Ser. No.08/600,306, a Continuation of patent application Ser. No. 08/100,573,file Feb. 12, 1996, now allowed, and in their copending patentapplication Ser. No. 08/555,589 filed on Nov. 13, 1995 and now pending.

[0051] When the operator has ascertained penetration of stem tip 1201′of stem member 1202′ into chest cavity 110, she or he advances slideablerod 1210′ relatively to hollow stem 1203′ by holding still with onehand, hollow stem 1203′ by its distal segment, and acting upon handle1211′ with his or her other hand so as to move rod 1210′ downwardly,toward chest cavity 110. The purpose of holding hollow stem 1203′ stilland firmly by its distal segment is to avoid accidental undulyadvancement of the device towards the heart. Rod handle 1211′ is thenadvanced to place webs 1222′ on the proper position on the epicardium.Being distal end 1218′ of rod 1210′ connected to proximal ends 1225′ ofelectrode-ribs 1216′, the downward movement of rod 1210′ will resultwith ejection end exit of electrode-ribs 1216′ through openings 1238′ ofstem tip 1201′. Rod 1210′ is retained in the chosen position byengagement of arrest tooth 1245″ of locking tab 1246′ on one of notches1209′ of rod 1210′. Engaged arrest tooth 1245″ of locking tab 1246′ willprevent backward and forward displacement of electrode-ribs 1216′. Uponejection of distal segments of ribs 1216′ from stem tip 1201′,electrode-ribs 1216′ as best seen in FIG. 2, will diverge outwardly onefrom another due, as already described, as a result of their resiliency.

[0052] Webs or pads 1222′ of each electrode ribs 1216′ pair will unfoldand spread between each pair of electrode-ribs to provide an electrodeof conductive surface of suitable size in contact with the heart.

[0053] As soon as deployed, webs or pads 1222′ are placed in contactwith the epicardium by downward resiliency of the ribs and or by theoperator pressing downward on handle 1206′ of device 1200′.

[0054] The distance between pads 1222′ on the epicardium can be suitablyadjusted by the operator acting upon handle 1211′ to advance or withdrawrod 1210′ slideable within hollow stem 1203′ to the desired positionsecured by tooth 1245″ of tab 1246′ which releasably engages notches1209′ of rod 1210′.

[0055] The device can also be rotated by the operator around itslongitudinal axis in order to position pads 1222′ on the desiredepicardial areas.

[0056] Insulated electrically conductive cable 1270′ are connected foruse to a defibrillator, a cardioconverter or a pacer to enablepercutaneous epicardial defibrillation, cardioversion or pacing. Sensingof cardiac electrical activity is provided by webs or pads 1222′.

[0057] Conductive surface 1260′ of web 1222′ can be provided withaccessories such as miniature or micro needles of conductive materialarranged in a brush like fashion capable of penetrating through theepicardial lining into the myocardium to provide a type of myocardialelectrode for myocardial defibrillation, cardioversion or pacing.

[0058] At completion of the electrical resuscitative effortselectrode-ribs 1216′ are withdrawn by withdrawing handle 1211′ of rod1210′, after manual release of locking tab 1246′ by action on handle1208′ to disengage tooth 1245″ from notches 1209′ of rod 1210′.

[0059]FIG. 4 shows an alternative form, generally indicated at 1600′, ofdevice 1200′ of FIG. 1 through 3. Structurally, alternative form 1600′differs from device 1200′ in having only one pair of electrode-ribswhich carries only one epicardial pad/sensor 4000. The single pad/sensor4000 is positioned on the epicardium, while another pad/sensor 4002 ispositioned on the skin of the back of the patient. Stem tip 1201′ hasopening 1272′ to allow exit of electrode-ribs pair 1216′. Access tochest cavity is gained precisely in the same way as with device 1200′ ofFIGS. 1 through 3. Insulated electrically conductive cable 1270′connected to epicardial pad 4000 as well as insulated electricallyconductive cable 1280′ connected to external pad 4002 on the skin of theback of the patient, are connected for use to a defibrillator, acardioconverter or a pacer to enable percutaneous epicardio-to-cutaneousdefibrillation, cardioversion or pacing. Sensing of cardiac electricalactivity can be provided by pads 4000 and 4002.

[0060] In FIGS. 5 through 9 is shown an alternative form, generallyindicated at 1070, of device 1200′, of FIGS. 1 to 3, in which thedefibrillating, pacing/sensing electrodes are applied to the expandablemember of a cardiac resuscitation device for percutaneous direct cardiacmassage. Such percutaneous direct cardiac massager is disclosed byZadini et Al. in their issued Pat. No. 5/466,221, in their copendingpatent application Ser. No. 008/100,573 filed on Jul. 30, 1993 allowedand abandoned, in their copending patent application Ser. No.08/600,306, a Continuation of patent application Ser. No. 08/100,573,file Feb. 12, 1996, now allowed, and in their copending patentapplication Ser. No. 08/555,589 filed on Nov. 13, 1995 and now pending.

[0061] Device 1070, as shown in FIG. 5, is composed of five maincomponents: a support case or member generally indicated at 1072, a stemmember or unit generally indicated at 1074, an intermediate membergenerally indicated at 700, an inflating-deflating means or devicegenerally indicated at 1008′ and an epicardial unit for electricalcardiac therapy generally indicated at 2000.

[0062] As best shown in FIG. 5, the support case 1072 is hollow and isof a generally tubular, cylindrical shape having a top wall 1073, a body801 and a distal end 5, including a narrow neck 6 and a flat, circularbase 7. The base 7 is preferably formed of transparent material toenable the operator to better visualize the actual position of the tip1502 of device 1070 on the anterior chest wall of the patient. Also,base 7 is formed with a central opening 31 to allow passage therethroughof stem 602 of the stem member 1074, as more fully described below.

[0063] The support case 1072 has a generally hollow cylindrical body 801encircling the intermediate member 700 and the stem member 1074.

[0064] As better shown in FIGS. 5 and 6, lever 854 encircles with itsexpanded head 857 support member 1072 at its midportion and is held inthat midportion by the presence of two annular rails 898 and 899. Lever854 carries a dog support 858 to which a dog 851 is pivotally securedvia a pin 856 and is provided with dog arrest 859 for dog 851. Dog 851projects through opening 853 of support member 1072 and reaches forratcheting engagement teeth 744 of annular rack 742 mounted on theintermediate member 700.

[0065] As shown in FIG. 5, tab 1080 is mounted on outer surface ofsupport member 1072 and is composed of pin 1082 and flexible arm 1084.Pin 1082 of tab 1080 is secured to support case 1072 and engages throughopening 864 annular recess 865.

[0066] The intermediate member 700 is interposed between the stem member1074 and the support case 1072 and is of generally cylindrical shape,with the female threaded portion 641 located approximately midway of thelength of support member 1072, and has an annular rack 742 extendingabout the exterior of the middle of the intermediate member 700,provided with a plurality of outwardly projecting teeth 744.

[0067] Stem member 1074 has a generally hollow cylindrical shape andcomprises body 613 and hollow stem 602.

[0068] Stem member 1074 is closed at its proximal end by top wall 1075.Body 613 of stem member 1074 is provided with a male threaded portion603 which mates with the female threaded portion 641 of the intermediatemember 700 as described above. Hollow stem 602 communicates with lowerend 615 of body 613 and projects through the base 7 of the support case1072 to communicate with stem tip 1502.

[0069] Spring or resilient member 280 is located within lower segment ofsupport case 1072, encircles hollow stem 602 and bears against lower end615 of support member 1074 to urge stem member 1074 upward.

[0070] Distal end 1012 of hose 1014 of inflating-deflating means 1008passes through longitudinal slit 1010 of support case 1072 and isconnected to stem 602 at window 1016. Longitudinal slit 1010 formed onwall of support case 1072 permits that insertion of distal end 1012 ofhose 1014 into stem 602 is maintained in use upon sliding of stem 602 inrespect of support case 1072. Three ways shut off valve 1018 is locatedat connection between distal end 1012 of hose 1014 and stem 602.

[0071] Inflating-deflating means or device 1008 is generally cylindricalin shape with top wall 1022, bottom wall 1024 and lateral pleated walls1026. Resilient member or spring 1028 is contained within device 1008 tomaintain lateral wall 1026 distended in its resting position prior touse. It is obvious that manually operated inflating deflating device1008 may be substituted by a power operated inflating-deflating device.

[0072] As best seen in FIG. 7, stem tip 1502 is composed of two parts:proximal part 1504 shaped as an inverted cup firmly attached to thedistal end of stem 602 of stem member 1074, and distal part or convexapex 1506. Convex apex 1506 is firmly attached to inner hollow stem 1508which is telescopically slideable in airtight fashion within hollow stem602 and has proximal opening 1522 Convex apex has circular edge 1510adapted to fit together with circular edge 1512 of circular opening 1514of proximal part 1504 of stem tip 1502 to form together a spheroidallyshaped stem tip 1502. Inner hollow stem 1508 has at least one distalopening 1516 within stem end 1502 in flow communication with expandablemember or balloon 1520 which is partially or fully contained in acontracted status within stem end 1502. Hollow inner stem 1508 alsoprovides lateral stability to expandable member 1520 upon its expansionin operation and also provides the device with means of direction, andallows the operator to have full control on the direction to be given tothe expandable member in respect to the position of the heart duringcompression-decompression.

[0073] As best seen in FIGS. 8 and 9, device 1074 is provided with twoelectrode-pads or patches 2001 mounted on the heart contacting surfaceof expandable member 1520. The two pads 2001 are pliable to allow to befolded within stem end 1502 and/or in distal segment of hollow stemmember 1508 together with balloon 1520 and to be deployed upon expansionof balloon 1520. Each pad 2001 is connected via coiled cable 2002 withinstems 1508 and stem 602 to air-sealingly exit through stem 602 and thenthrough the wall of support case 1072 to be connected to an electricaltherapy device such as a defibrillator/cardioconverter, to a pacer or toan electrocardiographic monitoring device.

[0074] As best shown in FIG. 5, cables 2002 are conveniently coiledwithin hollow stem 602 to not oppose, by uncoiling, the sliding,occurring during use, of inner hollow stem 1508 within hollow stem 602.

[0075] A fiberoptic cable can be inserted into hollow stems 602 and 1508to reach transparently made convex apex 1506 of stem tip 1502 to providevisualization of chest cavity organ and confirm proper positioning ofthe device tip 1502. As connecting cable 2002, the fiberoptic cable canexit stem 602 in an air sealingly fashion to be connected to an opticalmonitoring device. The fiberoptic cable can be withdrawn once the properposition of the tip 1502 has been ascertain to allow free passage of airor gas for the inflation-deflation of balloon 1520. Hollow stem 602,with its extension 1508, can also be used as pathway for theadministration of medication directly to the heart.

[0076] Description of operation of device of FIGS. 5 to 9.

[0077] After a small superficial incision is made on the anterior chestwall, which could be as small as one centimeter in length, to allow thatblunt end or spheroidally shaped stem tip 1502 wins the skin resistance,in the left parasternal region in a location of the skin correspondingto the intrathoracic anatomical area designated as “trigonum sinepleura”, blunt tip 1502 of the device is engaged into the skin incisionand is advanced by blunt dissection through the thickness of the chestwall by the operator.

[0078] The operator ratchets the lever 854 laterally, while keeping thebase 7 of the support case 1074 pressing steadily against the patient'schest. This action causes dog 851 to drive the teeth 744 on rack 742 torotate the intermediate member 700. Since the operator is preventingrotation of the stem member 1074, and since intermediate member 700 isprevented from advancing by pin 1082 projecting through opening 864 andengaging annular recess 865 of intermediate member 700, the rotation ofintermediate member 700 will cause threads 641 to interact with threads603 of the stem member 1074 to force stem member 1074 to advance stemtip 1502 through the chest wall structure 107 until stem tip 1502penetrates chest cavity 110. The gradual and controlled slow advancementof stem 1074 will result in penetration of stem tip 1502 into chestcavity 110. Once the passage of relatively broad stem end 1502 iscompleted, and relatively narrow stem 602 is engaged in the chest wallhole formed by stem end 1502, the operator will immediate tactuallysense entry of blunt stem tip 1502 into chest cavity 110 by the suddenfall of resistance to forward and sideways movements, said resistance toforward and sideways movements being present during passage of said stemtip 1502 through chest wall 107, due to constraint exerted by chest walltissues upon stem tip 1502 during its passage through chest wall 107.Blunt stem tip 1502 is therefore advanced through the thickness of chestwall 107 by blunt dissection until it enters the chest cavity by bluntdissection. Upon receipt of this signal, the operator will cease toactuate the lever 854.

[0079] The choice of the “trigonum sine pleura” prevents the insurgenceof pneumothorax, i.e. collapsing of the lungs, which inevitably occursevery time the pleural cavity is entered. With regard to the occurrenceof pneumothorax, due to the fact that the “trigonum sine pleura” is asubstantially restricted area, the choice of such area is onlymeaningful if the passage opened through the chest wall is significantlysmall, as it can be achieved with all the embodiments described in thisinvention. Being the width of this area invariably small, ordinarily inthe range of less than two/two and a half centimeter, it is criticalthat the heart compressing member which has to be passed through thechest wall to enter the chest cavity is contracted to a comparably smallsize, i.e. less than the width of the “trigonum sine pleura”.

[0080] As pointed out above, upon entry of blunt stem tip 1502 into thechest cavity, the operator will be alerted of the occurred entry of stemtip 1502. Balloon 1520 will then be inflated by the operator as follows.The operator will open valve 1018, then will compress pneumatic sourceor inflating-deflating device 1008. Air or suitable gas such as CO2 willflow into hollow inner stem through opening 1522 of inner hollow stem1508 and will exit through distal opening 1516 located within stem tip1502 to enter balloon 1520 enabling inflation of balloon or expandablemember 1520. As balloon 1520 begins to inflate, as seen in FIG. 8,hollow inner stem 1508, being telescopically slideable within hollowstem 602, will be dragged forward with convex apex 1506 to which isfirmly attached, being convex apex 1516 of stem tip 1502 being firmlyattached to the heart contacting surface of balloon 1520.

[0081]FIG. 9 shows balloon or expandable member or inflatable-deflatablemember 1520 inflated to the required pressure to achieve cardiaccompression.

[0082] As shown in FIGS. 8 and 9 pads 2001 will contact the epicardiumas soon as balloon 1520 begins to inflate. Besides providing guidance tothe direction of compression and decompression of the heart,telescopically sliding hollow stems 602 and 1508 provide also guidancefor proper placement of pads 2001 on the epicardium. The device at thispoint can be used by the operator both for direct compression of theheart and for electrical therapy. With this device both operations canbe conveniently carried out simultaneously.

[0083] As for device 1600′, in an alternative form here not illustratedbut easily inferable from device 1070, device 1070 can be provided witha single epicardial pad while the other pad is positioned externally onthe skin of the back of the patient. The epicardial pad can be eitherattached to the balloon or to stem tip convex apex 1506.

[0084]FIGS. 10 and 11 show an alternative form of device 1200′ of FIGS.1 through 4 in which the means for opening a passage via bluntdissection through the chest wall are physically separated from thedevice component used for electrical therapy.

[0085] The means for opening the passage through the chest wall or chestwall blunt dissector, generally indicated at 4500, is composed of handle4502, stem 4504 and dissecting blunt tip 4506. Handle 4502 is ofgenerally cylindrical hollow shape having proximal end 4508 and distalend 4510 and is firmly connected by distal end 4510 to hollow stem 4504of smaller diameter than handle 4502. Dissecting blunt tip of generallyspheroidal shape is firmly attached to distal end 4512 of hollow stem4504. Stem tip 4506 can be provided with opening 4514 in communicationwith the interior of hollow stem 4504 and handle 4502 for passage ofelectrode-ribs 4520. Electrode ribs 4520 are in all similar to electroderibs 1216′ of FIGS. 1 to 4 in design and operation.

[0086] In use chest wall blunt dissector 4500 is operated precisely asdevice 1200′ of FIGS. 1 to 4 up to the point when the operator hassensed entry of the blunt tip 4506 into the chest cavity. Upon reachingthe chest cavity by blunt dissection with chest wall blunt dissector4500, the operator introduces and advances electrode-ribs 4520 intohollow handle 4502 through hollow stem 4504, through openings 4514 oftip 4506 of chest wall blunt dissector 4500 to properly place pads 4522of electrode ribs 4520 onto the epicardium ready for use.

[0087] Alternatively chest wall blunt dissector 4500 can be withdrawnfrom the chest, once it has gained access into the chest cavity bycreating a hole through the chest wall, to leave a passage for thesubsequent step of introducing electrod-ribs 4520.

[0088] For this purpose chest wall blunt dissector can be made solidrather than hollow.

[0089]FIGS. 12 and 13 show an alternative form of the EpicardialPercutaneous Device for Electrical Cardiac Therapy of FIGS. 1 through 4in combination with an alternative form of the Cardiac ResuscitationDevice for Percutaneous Direct Cardiac Massage illustrated in FIGS. 5through 9. This type of Cardiac Resuscitation Device for PercutaneousDirect Cardiac Massage has been fully disclosed by Zadini et Al. intheir issued Pat. No. 5/466,221, in their copending patent applicationSer. No. 08/100,573 filed on Jul. 30, 1993 allowed and abandoned, intheir copending patent application Ser. No. 08/600,306, a Continuationof patent application Ser. No. 08/100,573, file Feb. 12, 1996, nowallowed, and in their copending patent application Ser. No. 08/555,589filed on Nov. 13, 1995 and now pending. Applicants here disclose themost important features in combination with the Epicardial PercutaneousDevice for Electrical Cardiac Therapy. As shown in FIG. 12, which is across sectional schematic view of the device, generally indicated at 1,is composed of support case 2, of generally cylindrical shape, and stemunit 100 coaxially slideable within support case 2, and electrical unit110. Stem unit or member 100 has, proximally, handle 111 formanipulation of the device and, distally, stem 102 with blunt stem tipor end 104, of general spheroidal shape, which houses, with the deviceat rest, expandable member or balloon 105. Within stem unit 100 iscontained in its proximal segment pneumatic container 129 for inflationof balloon 105 as it will be explained below. Lever 17 acts upon stemunit 100 to permit gradual controlled advancement of blunt stem tip 104of stem 102 into the chest cavity through chest wall 107. The numerousmechanisms of advancement, manual and automatic, as well as other safetyfeatures of the Cardiac Resuscitation Device for Percutaneous DirectCardiac Massage have already been described at length in the abovementioned patents and, although they are important features for thedesign and operation of the Epicardial Percutaneous Device forElectrical Cardiac Therapy, they have been omitted here because they arenot essential for the understanding of the use of the EpicardialPercutaneous Device for Electrical Cardiac Therapy. In use, as for thedevice 1070 of FIGS. 5 through 9, the operator, after the initial skinincision in the same areas of the anterior chest wall used for all thepreviously described devices, inserts stem tip or end 104 of device 1into the incision. He or she then acts upon lever 17 which, as aboveindicated, advances stem tip 104 through the thickness of the chest wall107. Stem tip 104, during its advancement, creates a passage through thethickness of chest wall 107 via blunt dissection, and enters bluntly andsafely due to its blunt features into chest cavity in front of theheart. At this point, as shown in FIG. 12, balloon or expandable member105 is automatically inflated to a fully inflated status as shown inFIGS. 12 and 13 by pneumatic container 129. Unlike device 1070 in whichcardiac compression is achieved by alternating inflation and deflationof the balloon, in this alternative form the balloon 105 is fullyinflated to a predetermined shape and size and maintained in suchexpanded status in order to provide a sufficiently rigid heartcontacting surface for direct cardiac massage. As shown in FIG. 13, theoperator by acting upon handle 111 will press stem unit 100 downwardcausing compression of the heart and, by releasing the downward pressureon handle 111, will cause decompression and blood refilling of theheart.

[0090] Conductive pliable or foldable or contractible pads 120 ofelectrical unit 110, connected to a defibrillator, cardioverter orpacer, or to an electrocardiographic monitoring device via cable 121,will contact the epicardium when balloon 105 will begin to inflate. Thedevice at this point can be used by the operator both for directcompression of the heart and for electrical therapy. As in device 1070of FIGS. 5 through 9 both operations can be conveniently carried outsimultaneously. As for device 1070 of FIG. 5 through 9, the device canbe provided with fiberoptic means of visualization for ascertaining ofproper positioning of the electrical pads on the epicardium.

What is claimed is:
 1. A cardiac resuscitation device comprising: atleast one electrode contacting the heart for electrical therapy of theheart, and means of blunt dissection of the chest wall to insert saidelectrode into the chest cavity.
 2. The cardiac resuscitation device ofclaim 1 further comprising: a heart contacting member for cardiaccompression, said heart contacting member being insertable into thechest cavity.
 3. A method for cardiac resuscitation comprising the stepsof: opening a passage into a chest cavity through a chest via means forblunt dissection through said chest wall, and applying at least oneelectrode directly on a surface of a heart through said passage.
 4. Themethod for cardiac resuscitation of claim 3 further comprising the stepof: inserting a heart contacting member for cardiac compression throughsaid passage for direct cardiac compression decompression.
 5. A cardiacresuscitation device comprising: at least one electrode contacting theheart for electrical therapy of the heart, and means for entering achest cavity by blunt dissection to insert said electrode into the chestcavity.
 6. The cardiac resuscitation device of claim 5 furthercomprising: a heart contacting member for cardiac compression, saidheart contacting member being insertable into said chest cavity.
 7. Amethod for cardiac resuscitation comprising the steps of: entering achest cavity by means for blunt dissection, inserting at least oneelectrode into said chest cavity, and applying said electrode directlyon a surface of a heart.
 8. The method for cardiac resuscitation ofclaim 7 further comprising the step of: inserting a heart contactingmember for cardiac compression into said chest cavity for direct cardiaccompression decompression.